Human beings are so curious about things around them. Things around us are related to one another. Some bodies are at rest and some are in motion. Rest and motion are interrelated terms.

In the previous classes you have learnt about various types of …

Light is a form of energy which travels in the form of waves. The path of light is called ray of light and group of these rays are called as beam of light. Any object which gives out light are termed as source of light. Some of the sources emit their …

Sun is the primary source of thermal energy for all living organisms. Thermal energy is the cause and temperature is the effect. All living organisms need a particular temperature for their survival. In the kitchen, a container with a steel bottom is …

You have already learnt about electricity in your lower classes, haven’t you? Well, electricity deals with the flow of electric charges through a conductor. As a common term it refers to a form of energy. The usage of electric current in our …

Sound plays a major role in our lives. We communicate with each other mainly through sound. In our daily life, we hear a variety of sounds produced by different sources like humans, animals, vehicle horns, etc. Hence, it becomes inevitable to …

Humans are very much interested in knowing about atoms. Things around us are made up of atoms. A Greek Philosopher ‘Democritus’ in 400 BC (BCE) believed that matter is made up of tiny indestructible units called atoms. Later, in 1803, …

You have learnt, in your lower classes that matter is around us everywhere. Matter is made of atoms. Curiously the idea of atom was first proposed by the Greek philosophers in the fifth century BC (BCE). But, their theory was more philosophical than …

The eighteenth and nineteenth centuries witnessed a rapid development in chemistry in all spheres of scientific activities. By 1860, scientists had already discovered 60 elements and determined their atomic masses. They noticed that some elements had …

You have learnt about mixtures in your lower classes. Most of the substances that we encounter in our daily life are mixtures of two or more substances. The substances present in a mixture may exist in one or more physical state. For example, when we …

As you know from your earlier studies, a chemical reaction involves breaking of old chemical bonds and formation of new chemical bonds. This change may happen spontaneously or it may be facilitated by external forces or energy. Chemistry is all about …

You have studied, in your lower classes, that carbon is an inseparable element in human life as we use innumerable number of carbon compounds in our day to day life. Because, the food we eat, medicines we take when ill, clothes we wear; domestic and …

• List the basic events of aerobic and anaerobic respiration
• List the basic events of aerobic and anaerobic respiration Plants exhibits varying degrees of organization. Atoms are organized into molecules, molecules into organelles, organelles into …

The variety in nature and habits of animals in the biosphere are quite amazing and interesting. What we see around us may be just few, but there are innumerable species living in this world. You have learnt in lower classes about the classification …

Multicellular organisms possess millions of cells in their body. Every cell needs a constant supply of essential substances like nutrients and oxygen to maintain life and survival. Food is the only source of energy and every cell gets its energy by …

One of the characteristic features of all living organisms is responding to stimuli. ‘Stimulus’ refers to the changes in the environmental condition, that are detected by receptors present in the body. Relevant changes in the activities …

The word hormone is derived from the Greek word “hormon” meaning “ to excite”. The function of control and coordination in plants is performed by chemical substances produced by the plants called plant hormones. In plants several cells are capable of …

“Living organisms cannot survive for an indefinite period on earth. All living organisms have the ability to produce more of its own kind by the process called reproduction. Reproduction is the unfolding of life forms where new individuals are …

“Like Begets Like” is an important and universal phenomenon of life as the living beings produce offspring of their own kind. Colour of eye, color of hair, shape of nose, type of earlobe, etc, are inheritable traits. Have you ever …

Living organisms possess distinct characteristics, display organisational and functional unity, entail a mechanism of origin and evolution of diversities and maintain a balanced relationship with nature. Most aspects of evolution indicate that the …

India’s population is likely to reach 1.7 billion by 2050. Current rate of India’s food production will be able to meet only 59% of the country’s food demand at that time. How can India feed 1.7 billion people by 2050? This can be …

Abuses occur in a variety of forms and are deeply rooted in cultural, social and economic practices. Solving this global problem however requires a much better understanding of its occurrence, causes and consequences with context to sexual and …

Environmental management deals with the different aspects of environment, its structure, function, its quality and its maintenance including conservation of its living and non-living components. The diversified natural resources on this earth provide …

In general, whenever we think of computers, the things that come to our mind is computer screen, keyboard, mouse and CPU. We learnt about computer and parts of a computer as introductory part in standard VI. Apart from that, software and hardware …